Dry cell



May 9, 193 3. I 5 STONE 1,908,194

DRY CELL Filed March 21, 1928 INVENTOR B w WW, {SW him q aLMn-rL ATTORNEYS Patented May 9, 1933 UNITED STATES PATENT OFFICES GEORGE STONE, OF KADISOH, WISCONSHV, ASSIGNOREO BURGESS BATTERY COMPANY,

A CORPORATION OF WISCONSIN Joni can.

Application filed larch 21, ms. Serial No. 263,274..

This invention relates to improvements in dr cells and methods of makingthem.

n the manufacture of dry cells it has been proposed to insert a washer of substantially the same diameter as the inner diameter of the zinc cup overthe cathode core slightly spaced 2 from the to of the coreto form an expansion space or gases formed during the discharge of the celL- A fusible seal is placed over this washer and the upper edge of the cup then crimped.

In some instances the frictional resistance between the washer and the wall of the can is depended on to hold the washer in its proper place. This requires the use of washers and cans ofexact dimensions, with the cans perfectly round. In actual practice, difiicultiesare encountered due to the wash-- ers slipping down too far in the cans or tilting too much to one side thereby making an uneven seal. Where the washers are inserted by hand this condition is aggravated by careless workmanship.

In a prior application of Howard D. Hodge (deceased), Serial No. 123,237 Apparatus for assembling galvanic cells now Patent No. 1,669,054 granted May 8, 1928), there is described and claimed a machine by means of which the variouscomponents of a dry cell .are inserted in a can as it is automatically fed past a number of stations. When the Hodge machine is employed in the assemblage of cells, defects due to careless workmanship in the placing of the washers is avoided and such defective insertion is entirely due to defective washers and cans. Furthermore, when theupper edge of the can is crimped, it apparently causes a slight bulge or distortion of the can at about the washer level and the washers then drop to the top of the core.

It has been proposed to overcome these difliculties by crimping or spinning a continuous shoulder at a slight distance below the top of the can on which the washer is adapted to rest. Such spinning or crimping of a continuous shoulder cannot be readily accomplished in a battery assembling machine, and, therefore, adds an extra step to and cell constructed in accordance wit my the manufacturing operation and adds to the cost of the cell. I

In In present invention, I indent the can a slight istance beneath the top preferably at circumferentially spaced intervals andthen crimp the upper edge of the can, preferably by spot crimpin and in staggered vertical arrangement witi the indentation.

In the drawing, I have shown a batte can invention.

Fig. 1 is a perspective view of the cup, and,

Fig. 2 is a vertical, sectional view of the completed cell. j

A dry cell constructed in accordance with my invention is shown in cross section in Fig. 2. It consists of a can 1 containin a depolarizing cathode core consisting o a central carbon rod 2 about which is uniformly tamped a depolarizing mix 3 of carbon or graphite and a depolarizer such as manganese dioxide, conductin salts and water. The cathode core may e naked or may be surrounded by a bibulous envelope 4 of cheesecloth, tissue paperor hardened dip such as is described in United States Patent, No. 1,316,597 and may be insulatedat the bottom by folding under the bibulous envelope. A suitable gelatinous or pasty electrolyte 5 separates the core from the can. This electrolyte may be that described in United States Patent, No. 1,292,764 and may be compounded as described in United States Patent, No. 1,370,056. An expansion. space 6 is provided above the top of the core and a waterproofed washer 7 is arranged over this expansion space to support a wax or pitch seal 8. As shown, the washer rests upon a seriesof circumferentially spaced indentations 9 arranged-in substantially the same horizontal 90 plane and adapted to limit the downward movement of the washer to retain it'suitably spaced from the top of the core. The

I ma be performed'by Lorig, filed suc as the apparatus described and claime in the copending application of Robert A. v March 21st, 1928, Serial No. 263,232 (now Patent No. 1,766,661, granted June 24,1930), 1 v

By forming spaced indentations, in'lieu of a COIltlIlllOllSShOllldGl, the operatioumay thus be accomplished on a battery assembling I machine of the Hodge or Lorig type and the crimp: in the upper edge of the can may likethe cell without necessitating a separate ater 7 wise e formed as a step in the assembla e of operation as is necessary when the can. is crimped I claim: In a dry cell, a zinc cu having a plurality of horizontally arrange circumferentially s aced indentations at a slight distance from.

t e top of the cup and havin its upper edge crimped at spaced intervals, e crimped portions of the upper edge testimon whereof I aflix'my si GEORGE sriiim.

mam, I

any suitable apparatusi I continuously around upper edge.

being staggered with resiplectto the indentations. j 

